Problem: Multiply. ${3}\times{9}=$
Explanation: Let's visualize to help us solve. The array shows ${3}$ rows with ${9}$ squares in each row. $1$ $2$ $3$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ ${3} \times {9} = \underbrace{{9} + {9} +{9}}_{{3}{\text{ nines}}} = 27}$ ${3}\times{9}=27}$